3 files changed, 53 insertions, 39 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 5732e13cd0da..27cf5577f239 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -182,7 +182,7 @@ int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page *page)
                 /* We requested READDIRPLUS, but the server doesn't grok it */
                 if (error == -ENOTSUPP && desc->plus) {
                         NFS_SERVER(inode)->caps &= ~NFS_CAP_READDIRPLUS;
-                        NFS_FLAGS(inode) &= ~NFS_INO_ADVISE_RDPLUS;
+                        clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode));
                         desc->plus = 0;
                         goto again;
                 }
@@ -545,7 +545,7 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
                         break;
                 }
                 if (res == -ETOOSMALL && desc->plus) {
-                        NFS_FLAGS(inode) &= ~NFS_INO_ADVISE_RDPLUS;
+                        clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode));
                         nfs_zap_caches(inode);
                         desc->plus = 0;
                         desc->entry->eof = 0;
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 622184553516..ee27578277f3 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -739,7 +739,7 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
                         inode->i_fop = &nfs_dir_operations;
                         if (nfs_server_capable(inode, NFS_CAP_READDIRPLUS)
                             && fattr->size <= NFS_LIMIT_READDIRPLUS)
-                                NFS_FLAGS(inode) |= NFS_INO_ADVISE_RDPLUS;
+                                set_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode));
                 } else if (S_ISLNK(inode->i_mode))
                         inode->i_op = &nfs_symlink_inode_operations;
                 else
@@ -849,26 +849,43 @@ void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)
         }
 }
 
+static int nfs_wait_schedule(void *word)
+{
+        if (signal_pending(current))
+                return -ERESTARTSYS;
+        schedule();
+        return 0;
+}
+
 /*
  * Wait for the inode to get unlocked.
- * (Used for NFS_INO_LOCKED and NFS_INO_REVALIDATING).
  */
-static int
-nfs_wait_on_inode(struct inode *inode, int flag)
+static int nfs_wait_on_inode(struct inode *inode)
 {
         struct rpc_clnt *clnt = NFS_CLIENT(inode);
         struct nfs_inode *nfsi = NFS_I(inode);
-
+        sigset_t oldmask;
         int error;
-        if (!(NFS_FLAGS(inode) & flag))
-                return 0;
+
         atomic_inc(&inode->i_count);
-        error = nfs_wait_event(clnt, nfsi->nfs_i_wait,
-                                !(NFS_FLAGS(inode) & flag));
+        rpc_clnt_sigmask(clnt, &oldmask);
+        error = wait_on_bit_lock(&nfsi->flags, NFS_INO_REVALIDATING,
+                                        nfs_wait_schedule, TASK_INTERRUPTIBLE);
+        rpc_clnt_sigunmask(clnt, &oldmask);
         iput(inode);
+
         return error;
 }
 
+static void nfs_wake_up_inode(struct inode *inode)
+{
+        struct nfs_inode *nfsi = NFS_I(inode);
+
+        clear_bit(NFS_INO_REVALIDATING, &nfsi->flags);
+        smp_mb__after_clear_bit();
+        wake_up_bit(&nfsi->flags, NFS_INO_REVALIDATING);
+}
+
 int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 {
         struct inode *inode = dentry->d_inode;
@@ -1029,18 +1046,19 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
         if (NFS_STALE(inode))
                 goto out_nowait;
 
-        while (NFS_REVALIDATING(inode)) {
-                status = nfs_wait_on_inode(inode, NFS_INO_REVALIDATING);
-                if (status < 0)
-                        goto out_nowait;
-                if (NFS_ATTRTIMEO(inode) == 0)
-                        continue;
-                if (nfsi->cache_validity & (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ATIME))
-                        continue;
-                status = NFS_STALE(inode) ? -ESTALE : 0;
-                goto out_nowait;
+        status = nfs_wait_on_inode(inode);
+        if (status < 0)
+                goto out;
+        if (NFS_STALE(inode)) {
+                status = -ESTALE;
+                /* Do we trust the cached ESTALE? */
+                if (NFS_ATTRTIMEO(inode) != 0) {
+                        if (nfsi->cache_validity & (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ATIME)) {
+                                /* no */
+                        } else
+                                goto out;
+                }
         }
-        NFS_FLAGS(inode) |= NFS_INO_REVALIDATING;
 
         /* Protect against RPC races by saving the change attribute */
         verifier = nfs_save_change_attribute(inode);
@@ -1052,7 +1070,7 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
                 if (status == -ESTALE) {
                         nfs_zap_caches(inode);
                         if (!S_ISDIR(inode->i_mode))
-                                NFS_FLAGS(inode) |= NFS_INO_STALE;
+                                set_bit(NFS_INO_STALE, &NFS_FLAGS(inode));
                 }
                 goto out;
         }
@@ -1083,9 +1101,9 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
                 inode->i_sb->s_id,
                 (long long)NFS_FILEID(inode));
 
-out:
-        NFS_FLAGS(inode) &= ~NFS_INO_REVALIDATING;
-        wake_up(&nfsi->nfs_i_wait);
+ out:
+        nfs_wake_up_inode(inode);
+
  out_nowait:
         unlock_kernel();
         return status;
@@ -1404,7 +1422,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr, unsign
          */
         nfs_invalidate_inode(inode);
  out_err:
-        NFS_FLAGS(inode) |= NFS_INO_STALE;
+        set_bit(NFS_INO_STALE, &NFS_FLAGS(inode));
         return -ESTALE;
 }
 
@@ -1996,7 +2014,6 @@ static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
                 nfsi->ndirty = 0;
                 nfsi->ncommit = 0;
                 nfsi->npages = 0;
-                init_waitqueue_head(&nfsi->nfs_i_wait);
                 nfs4_init_once(nfsi);
         }
 }
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 229a1755842a..deef9567788a 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -112,8 +112,8 @@ struct nfs_inode {
         /*
          * Various flags
          */
-        unsigned int            flags;
-        unsigned long           cache_validity;
+        unsigned long           flags;                  /* atomic bit ops */
+        unsigned long           cache_validity;         /* bit mask */
 
         /*
          * read_cache_jiffies is when we started read-caching this inode,
@@ -175,8 +175,6 @@ struct nfs_inode {
         /* Open contexts for shared mmap writes */
         struct list_head        open_files;
 
-        wait_queue_head_t       nfs_i_wait;
-
 #ifdef CONFIG_NFS_V4
         struct nfs4_cached_acl  *nfs4_acl;
         /* NFSv4 state */
@@ -199,11 +197,11 @@ struct nfs_inode {
 #define NFS_INO_REVAL_PAGECACHE 0x0020          /* must revalidate pagecache */
 
 /*
- * Legal values of flags field
+ * Bit offsets in flags field
  */
-#define NFS_INO_REVALIDATING    0x0001          /* revalidating attrs */
-#define NFS_INO_ADVISE_RDPLUS   0x0002          /* advise readdirplus */
-#define NFS_INO_STALE           0x0004          /* possible stale inode */
+#define NFS_INO_REVALIDATING    (0)             /* revalidating attrs */
+#define NFS_INO_ADVISE_RDPLUS   (1)             /* advise readdirplus */
+#define NFS_INO_STALE           (2)             /* possible stale inode */
 
 static inline struct nfs_inode *NFS_I(struct inode *inode)
 {
@@ -229,8 +227,7 @@ static inline struct nfs_inode *NFS_I(struct inode *inode)
 #define NFS_ATTRTIMEO_UPDATE(inode)     (NFS_I(inode)->attrtimeo_timestamp)
 
 #define NFS_FLAGS(inode)                (NFS_I(inode)->flags)
-#define NFS_REVALIDATING(inode)         (NFS_FLAGS(inode) & NFS_INO_REVALIDATING)
-#define NFS_STALE(inode)                (NFS_FLAGS(inode) & NFS_INO_STALE)
+#define NFS_STALE(inode)                (test_bit(NFS_INO_STALE, &NFS_FLAGS(inode)))
 
 #define NFS_FILEID(inode)               (NFS_I(inode)->fileid)
 
@@ -252,7 +249,7 @@ static inline int nfs_server_capable(struct inode *inode, int cap)
 
 static inline int NFS_USE_READDIRPLUS(struct inode *inode)
 {
-        return NFS_FLAGS(inode) & NFS_INO_ADVISE_RDPLUS;
+        return test_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode));
 }
 
 /**